returns a vertex of the biconnected components graph corresponding to a given vertex of the original graph and belonging to the representation of a certain biconnected component given by a vertex of the BC-tree. More...

Array that contains for each BC-tree-vertex the representant of its parent within the subgraph in the biconnected components graph belonging to the biconnected component represented by the respective BC-tree-vertex. More...

Array that contains for each BC-tree-vertex the representant of itself within the subgraph in the biconnected components graph belonging to the biconnected component represented by the parent of the respective BC-tree-vertex. More...

Enumeration type for characterizing the vertices of the original graph. More...

Detailed Description

Linear-time implementation of dynamic SPQR-trees.

The class DynamicSPQRTree maintains the arrangement of the triconnected components of a biconnected multi-graph G [Hopcroft, Tarjan 1973] as a so-called SPQR tree T [Fi Battista, Tamassia, 1996]. We call G the original graph of T. The class DynamicSPQRTree supports the statical construction of an SPQR-tree for a given graph G, and supports dynamic updates, too.

Each node of the tree has an associated type (represented by SPQRTree::NodeType), which is either SNode, PNode, or RNode, and a skeleton (represented by the class DynamicSkeleton). The skeletons of the nodes of T are in one-to-one correspondence to the triconnected components of G, i.e., S-nodes correspond to polygons, P-nodes to bonds, and R-nodes to triconnected graphs.

In our representation of SPQR-trees, Q-nodes are omitted. Instead, the skeleton S of a node v in T contains two types of edges: real edges, which correspond to edges in G, and virtual edges, which correspond to edges in T having v as an endpoint. There is a special edge er in G at which T is rooted, i.e., the root node of T is the node whose skeleton contains the real edge corresponding to er.

The reference edge of the skeleton of the root node is er, the reference edge of the skeleton S of a non-root node v is the virtual edge in S that corresponds to the tree edge (parent(v),v).